Enum HttpDownloadState

pub enum HttpDownloadState {
    Init {
        url: Url,
    },
    Resolving {
        dns: DnsResolveState,
        host: String,
        port: u16,
        path: String,
        query: Option<String>,
    },
    Connecting {
        tcp: TcpConnState,
        ip: Ipv4Addr,
        port: u16,
        host_header: String,
        request_uri: String,
    },
    SendingRequest {
        socket_handle: usize,
        request: Vec<u8>,
        sent: usize,
        start_tsc: TscTimestamp,
    },
    ReceivingHeaders {
        socket_handle: usize,
        accumulator: HeaderAccumulator,
        start_tsc: TscTimestamp,
    },
    ReceivingBody {
        socket_handle: usize,
        response_info: HttpResponseInfo,
        received: usize,
        start_tsc: TscTimestamp,
        last_activity_tsc: TscTimestamp,
    },
    Done {
        response_info: HttpResponseInfo,
        total_bytes: usize,
    },
    Failed {
        error: HttpError,
    },
}

HTTP download state machine.

Orchestrates DNS resolution → TCP connection → HTTP request/response. Supports streaming for large downloads.

Variants

Init

Initial state with target URL.

Fields

url: Url

Resolving

Resolving hostname to IP address.

Fields

dns: DnsResolveState

DNS state machine

host: String

Target host

port: u16

Target port

path: String

Request path

query: Option<String>

Query string (if any)

Connecting

Connecting to server.

Fields

tcp: TcpConnState

TCP state machine

ip: Ipv4Addr

Resolved IP

port: u16

Target port

host_header: String

Host header value

request_uri: String

Request path + query

SendingRequest

Sending HTTP request.

Fields

socket_handle: usize

Socket handle

request: Vec<u8>

Serialized HTTP request

sent: usize

Bytes sent so far

start_tsc: TscTimestamp

When send started

ReceivingHeaders

Receiving HTTP response headers.

Fields

socket_handle: usize

Socket handle

accumulator: HeaderAccumulator

Header accumulator

start_tsc: TscTimestamp

When receive started

ReceivingBody

Receiving HTTP response body.

Fields

socket_handle: usize

Socket handle

response_info: HttpResponseInfo

Response info from headers

received: usize

Bytes received so far

start_tsc: TscTimestamp

When body receive started

last_activity_tsc: TscTimestamp

Last activity time (for idle timeout)

Done

Download complete.

Fields

response_info: HttpResponseInfo

Response info

total_bytes: usize

Total bytes received (body only)

Failed

Download failed.

Fields

error: HttpError

Error details

Implementations

impl HttpDownloadState

pub fn new(url: Url) -> Result<Self, HttpError>

Create new HTTP download state machine.

pub fn start(&mut self, _now_tsc: u64)

Start the download.

Transitions from Init to Resolving (or Connecting if IP known).

pub fn step( &mut self, dns_result: Result<Option<Ipv4Addr>, ()>, tcp_state: TcpSocketState, recv_data: Option<&[u8]>, _can_send: bool, now_tsc: u64, dns_timeout: u64, tcp_timeout: u64, http_send_timeout: u64, http_recv_timeout: u64, ) -> StepResult

Step the state machine.

Arguments

• dns_result: Result from smoltcp DNS query (if resolving)
• tcp_state: Current TCP socket state (if connected)
• recv_data: Data received from socket (if any)
• can_send: Whether socket can accept more data
• now_tsc: Current TSC value
• timeouts: Timeout configuration (DNS, TCP, HTTP timeouts)

Returns

• Pending: Still in progress
• Done: Download complete, call result() for info
• Timeout: Operation timed out
• Failed: Operation failed, call error() for details

Callback

When recv_data contains body data during ReceivingBody state, the caller should pass that data to the storage layer.

fn step_inner( &self, current: HttpDownloadState, dns_result: Result<Option<Ipv4Addr>, ()>, tcp_state: TcpSocketState, recv_data: Option<&[u8]>, _can_send: bool, now_tsc: u64, dns_timeout: u64, tcp_timeout: u64, http_send_timeout: u64, http_recv_timeout: u64, ) -> (HttpDownloadState, StepResult)

Internal step implementation.

fn build_request(host: &str, request_uri: &str) -> Vec<u8>

Build HTTP GET request.

pub fn request_bytes(&self) -> Option<(&[u8], usize)>

Get the request bytes to send (for SendingRequest state).

pub fn mark_sent(&mut self, additional: usize)

Update bytes sent (for SendingRequest state).

pub fn socket_handle(&self) -> Option<usize>

Get socket handle (if connected).

pub fn progress(&self) -> Option<HttpProgress>

Get download progress.

pub fn response_info(&self) -> Option<&HttpResponseInfo>

Get response info (if headers received).

pub fn result(&self) -> Option<(&HttpResponseInfo, usize)>

Get result (if complete).

pub fn error(&self) -> Option<&HttpError>

Get error (if failed).

pub fn is_terminal(&self) -> bool

Check if download is complete (success or failure).

pub fn is_active(&self) -> bool

Check if download is in progress.

Trait Implementations

impl Debug for HttpDownloadState

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for HttpDownloadState

fn default() -> Self

Returns the “default value” for a type.